and legitimate, it is the most easy thing in the world, to define every substantial entity whatever, because in order to do it, you have only to observe its operations, give the most remarkable one a name, and define it by that name. By the help of this instruction only, you may make every peasant a consummate philosopher, and enable him to define the nature of all the entities in the universe. SECT. IX. XXXIX. These reflexions answer no other purpose, than that of confronting here and there a superficial and bastard schoolman, for all capable people know and confess, that we are unable to give a definition of any one substantial entity, except man. To what straight limits then is our philosophy confined! XL. But the misfortune is, that we have no certainty, that the general received definition of a man, to wit, that he is a _rational animal_, is a good and unexceptionable one; for we are clear it would not be a good one, if this faculty appertains to other animals as well as him, and it is matter of doubt whether it does or not; but I will not, nor cannot, in support of this doubt, avail myself of the authority of Porphyrus, who in his Treatise on Predicables, supposes God to be a rational animal; and in order to distinguish between God and man, defines man to be a mortal rational animal, because he thought that without the addition of the word mortal, the definition would be applicable to God as well as man. Neither will I avail myself of the authority of Aristotle, from whose second book, De Sect. Pythagora, Jamblicus cites these words: _Animalis rationalis aliud quidem est Deus, aliud autem homo._ But I may for this purpose, avail myself of the authority of some Fathers, among whom is St. Austin, who all affirm, that the angels are corporeal, or at least have doubted of their incorporeality; to which doubt, appertains that, of whether angels are rational animals, for in order to suppose them so, there wants nothing but their being corporeal, and consequently it is doubtful, whether the definition of rational animal, appertains solely to man.